Subsurface safety valve

• US 3,889,751 A
• Filed: 02/01/1974
• Issued: 06/17/1975
• Est. Priority Date: 02/01/1974
• Status: Expired due to Term

• Current Assignee: Beldon A. Peters
• Original Assignee: Beldon A. Peters
• Inventors: Peters, Beldon A.
• Primary Examiner(s): Leppink, James A.
• Application Number:
  US05/438,889
• Time in Patent Office: 501 Days
• Field of Search: 166/224A 251/75,359,367
• US Class Current: 166/319
• CPC Class Codes: E21B 34/08 responsive to flow or pressure of the fluid obtained E21B34/10 takes precedence

Abstract

A subsurface safety valve for use in a well production tubing. A tubular valve housing has a valve seat formed on one end and an interior tubular sliding member. A valve element is located on the sliding member for engagement with the valve seat for valve closure and contains openings above the valve element to permit flow through the valve housing when the valve is open. Spring means is provided between the sliding member and the valve housing and means cooperate with the spring means to cause snap action positive closure of the valve element on the valve seat. The spring means is arranged so that large flow areas are provided where the valve closure is made. The valve seat (or the valve element) is a resilient member and forms a resilient seal with the valve element (or valve seat) which resiliency permits the valve closure to be made on a surface which may be irregularly eroded.

Claims

1. A subsurface safety valve for use in controlling flow of well fluids through well pipe, comprising:

a valve housing connected to said well pipe;

a valve seat arranged on said valve housing;

a tubular sliding member slidable in said valve housing;

a valve element arranged on said sliding member for engagement with said valve seat, said sliding member having openings therein above said valve element to permit flow through said sliding member and said valve housing when the valve is open and to prevent flow through said sliding member and said valve housing when said valve element and said valve seat are engaged;

a plurality of spring means arranged between said sliding member and said valve housing; and

means cooperating with said spring means and said valve housing and said sliding member to cause snap action positive closure of said valve element on said valve seat, including means for urging each of said spring means independently of each other.

2. A subsurface safety valve as recited in claim 1 in which said means cooperating to cause snap action positive closure of said valve element on said valve seat comprises:

a retaining recessed groove formed on the outer surface of said sliding member, said sliding member having two spaced apart shoulders formed thereon;

upper and lower springs arranged in the chamber between said sliding member and said valve housing;

a ball housing connected to said sliding member;

balls secured in said ball housing;

said inner wall of said valve housing containing a grooved recess, said balls being lodged in said recess of said valve housing when said sliding member is extended and fluids flow through said openings and said valve housing, differential flow across said flow orifice urging said sliding member upwardly and compressing said springs until said groove in said sliding member is adjacent said ball housing and said balls permitting thereby said sliding member to move rapidly upwardly against the force of only said upper spring.

3. A subsurface safety valve as recited in claim 1 including spaced apart grooves formed on said sliding member:

spaced apart grooves formed on the inner wall of said valve housing, said valve housing also having an inwardly extending shoulder between said grooves formed thereon;

spaced apart ball housings containing balls arranged on said sliding member and movable therewith;

upper and lower spaced apart springs arranged in the space between said sliding member and the inner wall of said housing, said upper spring being above said upper ball housing and said lower spring being between said shoulder and said lower ball housing whereby upward movement of said sliding member relative to said valve housing compresses said springs untIl said balls are opposite recesses in said valve housing at which time said sliding member is permitted to move upwardly free of the bias of said springs.

4. A subsurface safety valve as recited in claim 1 in which said means cooperating to cause snap action positive closure of said valve element on said valve seat comprises:

a retaining recessed groove formed on the outer surface of said sliding member, said sliding member having two spaced apart shoulders formed thereon;

a plurality of springs arranged in the chamber between said sliding member and said valve housing;

a ball housing connected to said sliding member;

balls secured in said ball housing;

said inner wall of said valve housing containing a grooved recess, said balls being lodged in said recess of said valve housing when said sliding member is extended and fluids flow through said openings and said valve housing, differential flow across said flow orifice urging said sliding member upwardly and compressing said springs until said groove in said sliding member is adjacent said ball housing and said balls permitting thereby said sliding member to move rapidly upwardly against lesser spring force.

5. A subsurface safety valve as recited in claim 1 including spaced apart grooves formed on said sliding member:

spaced apart grooves formed on the inner wall of said valve housing, said valve housing also having an inwardly extending shoulder between said grooves formed thereon;

spaced apart ball housings containing balls arranged on said sliding member and movable therewith;

a plurality of spaced apart springs arranged in the space between said sliding member and the inner wall of said housing at least one of said springs being above said upper ball housing and one spring being between said shoulder and said lower ball housing whereby upward movement of said sliding member relative to said valve housing compresses said springs until said balls are opposite recesses in said valve housing at which time said sliding member is permitted to move upwardly free of the bias of said springs.

6. A subsurface safety valve as recited in claim 1, in which, said valve seat or said valve element is positioned away from the direct flow of said well fluids when said valve is open.

7. A subsurface safety valve as recited in claim 6 in which said valve seat is formed of resilient material.

8. A subsurface safety valve as recited in claim 6 in which said valve element is formed of resilient material.

9. A subsurface safety valve as recited in claim 6 in which said valve element is tapered and formed of hard metal.

10. A subsurface safety valve for use in controlling flow of well fluids through well pipe comprising:

a valve housing connected to said well pipe;

a valve seat arranged on said valve housing;

a tubular sliding member slidable in said valve housing;

a tapered valve element formed of hard metal arranged on said sliding member for engagement with said valve seat, said sliding member having openings therein above said valve element to permit flow through said sliding member and said valve housing when the valve is open and to prevent flow through said sliding member and said valve housing when said valve element and said valve seat are engaged;

spring means arranged between said sliding member and said valve housing;

means cooperating with said spring means and said valve housing and said sliding member to cause snap action positive closure of said valve element on said valve seat;

a retractable sleeve arranged between said sliding member and said valve housing; and

a shoulder formed on said sliding member adjacent said tapered valve element for engaging said sleeve and moving it away from the lip of said valve seat.